Eating
The kelp tax
How food works in the habitats: what is grown, what is imported, and what is, very politely, never offered.
Most of what you will eat in the first months is cultivated kelp and habitat-grown protein. Surface-imported food exists; it is expensive, slightly resented, and reserved for occasions.
Cultivated
The shelf kelps are the spine of the local diet. They are bland in a way that is restful after the surface, and they cook in roughly four ways. You will learn the four ways.
Imported
Cured meats, hard cheeses, dried legumes — anything that travels well at one atmosphere and survives a long pressurisation cycle. These arrive on the quarterly tender and are gone within a week.
Pelagine
Do not ask. The Pelagine eat, but the question of what they eat — and whether any of it would be edible to a human — is one the Tyrian Court has politely declined to discuss in any detail. Conservancy etiquette is to never raise it. You will not be served Pelagine food. You will not be offered it. If, somehow, it is offered, decline.